ANYONE in a long-term relationship will tell you that, at times, men are indeed from Mars, and women are almost certainly from Venus. It's common knowledge that the sexes often think very differently, but until recently these differences were explained by the action of adult sex hormones or by social pressures which encouraged males and females to behave in a certain way. For the most part, the basic architecture of the brain, and its fundamental workings, were thought to be the same for both sexes.
Increasingly, though, those assumptions are being challenged. Research is revealing that male and female brains are built from markedly different genetic blueprints, which create numerous anatomical differences. There are also differences in the circuitry that wires them up and the chemicals that transmit messages between neurons. All this is pointing towards the conclusion that there is not just one kind of human brain, but two.
It's giving neuroscientists something of a headache. Most of what we know about the brain comes from studies of male animals and male human volunteers. If even a small proportion of what has been inferred from these studies does not apply to females, it means a huge body of research has been built on shaky foundations. Working out exactly how women are different could explain some long-running mysteries, such as why men and women are prone to different mental health problems and why some drugs work well for one sex but have little effect on the other.
Men Are from Mars, Women Are from Venus (published in May 1992) is a book by John Gray offering many suggestions for improving husband-wife relationships by understanding the communication style and emotional needs of the opposite gender. It spawned a series of follow-on books expanding on specific situations (see below).
The book, as suggested by the title, asserts the notion that men and women are as different as beings from other planets. Gray adopts this metaphor as the central theme of all his books and seminars, likening men and women to the classical Roman god Mars and goddess Venus as ideal types.
In contrast to some psychologists (and feminists) who emphasize similarities between the sexes, Gray writes almost exclusively about differences. Gray says that his "Martians" and "Venusians" are only stereotypes and cannot be applied blindly to individuals.
An example of the theories it offers is that women complain about problems because they want their problems to be acknowledged, while men complain about problems because they are asking for solutions. Other concepts in the book are the difference between women and men's point systems and how they react under stress.
The point system
Gray suggests that men and women count (or score) the giving and receiving of love differently. For men, they tend to give larger blocks of points (20, 30, 40 points etc.) whereas for women they give each act of love one point at a time.
Men and women each monitor the amount of give and take in a relationship and if the balance becomes off and one person feels they have given more than they have been given to, resentment flu develops. This is a time when communication is very important to help bring the relationship back into balance.
Example: A man might count a $200 present as 20 points, but a woman will count each individual piece of the present as 1 point each. For her, the total sum of points comes from the present as a whole. For example, the different parts of the environment where the present is given each get 1 point (candles, music, privacy, location etc.) the card gets 1 point, the flowers get 1 point, the gift wrap gets 1 point and the gift itself gets 1 point. Their totals may even out to be the same, but it's the act of scoring that is different.
The emotional stroke delivered by the sincere attention is as important as the value of the item. This can lead to conflict when a man thinks his work has earned 20 points and deserves appropriate recognition while the female has only given him 1 point and recognizes him accordingly.
 The cave and the wave
Another major point of Gray's books are the differences in the way they react under stress. He believes that many men withdraw until they find a solution to the problem. He refers to this as "retreating into their cave." In some cases they may literally retreat, for example, to the garage or spend time with friends. The point of retreating is to take time to determine a solution. What is known is that men in their caves are not necessarily focused on the problem at hand, many times this is a "time-out" of sorts to allow them to distance themselves from the problems so their brains can focus on something else. This allows them to revisit the problem later with a fresh perspective.
This has historically been hard for women to understand because when they are stressed their natural reaction is to talk about issues in order to find a solution. This leads to a natural dynamic of the man retreating as the woman tries to grow closer. This becomes a major source of conflict between any man and woman.
The wave is a natural cycle for women that is centered around their abilities to give to other people. When they feel full of love and energy to give to others their wave is in a stable place. As they give to others (and don't receive the same amount of love and attention given to them in return) their wave begins to grow until it eventually crashes. This is a time when a woman feels she has nothing else to give to those in her life and she needs the love of those around her (including self love) to help come out of this dark place. Once she is rejuvenated (by getting the support she needs) she is able to pop out of this dark place and once again has love and energy to give.
As one reviewer put it:
When men go into their cave, they are actually going through a phase of their relationship with a woman, when they want to be left alone. Any woman who has wondered why a boyfriend is not emailing/calling/messaging/meeting her will know what it feels like to be shut out of the cave. Women and 'the wave' is a concept [which] means that women go through periodic phases when they are unable to keep up their spirits without help and assistance from understanding men. At such times, 'the wave' crashes, and it needs to be given love and reassurance to rise up again with its usual confidence. 
 Critical response
Some researchers agree with Gray's ideas about male-female communications differences. Deborah Tannen's studies of male/female communication find that "for women, talk creates intimacy... But men live in a hierarchical world, where talk maintains independence and status." . However, other studies do not find such differences. Erina MacGeorge found only a 2 percent difference between communication styles and argues that "when it comes to comforting, the Mars-Venus concept is not only wrong, but harmful. For the most part, men and women use, and strongly prefer, the same ways of comforting others – listening, sympathizing and giving thoughtful advice."
Some feminists have criticized the book for being sexist and patronizing  When discussing relations with the opposite sex, one often hears the complaint, "It's like she's from another planet!", while others accuse it of being written as a 'self-improvement' book for women, blatantly suggesting that women should adapt to men's ways of communicating, rather than both genders co-operating. Susan Hamson's web site "The Rebuttal From Uranus" says:
"Despite its promotional hype, at its very core it is a sexist, patronizing, male-centered invective which does little more than perpetuate long-held negative gender stereotypes"
Hamson objects to the lack of reference and details about the research Gray claims to have made, as well as to two central points which she feels Gray makes in his book:
"that men fulfill active roles and are seen as ambitious and powerful. Women, however, satisfy passive roles"; and,
"although the author may grudgingly admit that women are cognizant human beings, they must necessarily take a back seat to the dominant male in their lives in order to routinely accommodate his wants and desires."